Prevent ochratoxin A in stored grain
Ochratoxin A is a mycotoxin that can cause health problems, such as kidney damage, in people and animals. A mycotoxin is a toxin produced by fungi that grow in certain conditions. Ochratoxin A can be found in cereal grains and other food products like coffee, grapes and pork. Keeping ochratoxin A out of grain is crucial to maintaining Canada’s reputation for exporting safe, high quality grain.
You can prevent ochratoxin A using the same practices you already use to keep your grain in good condition during storage: keep temperature and moisture content low and aerate your grain regularly.
What are safe moisture levels for your crop? The Official Grain Grading Guide's specifications for acceptable moisture in commonly grown cereal grains are:
- barley - malting: less than 13.6%
- barley - food, covered: less than 13.6%
- barley - food, hulless: less than 14.1%
- barley - general purpose, covered and hulless: less than 14.9%
- wheat (all classes): less than 14.6%
- oats (all classes): less than 13.6%
Conditions for ochratoxin A development
In Canada, a fungus called Penicillium verrucosum produces ochratoxin A. It develops in stored grain if the temperature and moisture content of the grain are above the recommended safe storage guidelines for that grain. Ochratoxin A and the fungus that produces it don't cause visible damage to grain and can't be detected through visual inspection.
Limits for ochratoxin A in grain exports
For many countries, the maximum allowable limit of ochratoxin A in grain is just five parts per billion. Buyers of Canadian grain use technology that can test for ochratoxin A at these very low concentrations.
Data collected each year from our monitoring program shows that the levels of ochratoxin A in Canada's grain are generally below these strict international limits. More than two decades of monitoring showed that the average amount of ochratoxin A in samples tested was less than one part per billion.
Ochratoxin A in foods sold in Canada
In 2025, Health Canada published an updated health risk assessment of ochratoxin A in foods. The assessment concluded that the dietary exposure to ochratoxin A for people living in Canada is of low concern and that the implementation of regulatory maximum levels in Canada is not needed at this time. If new information emerges that raises concerns, Health Canada will revisit the need for establishing maximum levels.
Contact us
For more information about preventing ochratoxin A in stored grain, contact Grain sanitation and infestation control.